Devil Beside You
by Tiayumi
Summary: He was his little brother and at the same time, he was his teacher at school, and to add even more variables to the equation, Rin was a demon whereas Yukio was a human and an exorcist. How could this be even more complicated? YukioxRin, Twincest
1. Dysfunctional Family

**A/N:** Hello everyone ~ After writing my first oneshot about Yukio/Rin, I couldn't help myself writing this fic XD I love them so much so it needed to be done ;o; This story should be a short one, something like 5 chapters, but depending on the support I have it might be extending XD Also, it is  rated M because I will write about incest, sex and some other happy stuff like that ~

* * *

 **Devil Beside You**

 _Chapter 1: Dysfunctional Family_

"Nii-san, get up."

Rin Okumura was sleeping; his messy jet-black head standing out from his bed with his pillow firmly held in his arms like a kid. Sighing, his younger brother shook him up, once again, yet Rin barely moved an inch.

"Are you serious?" groaned Yukio, giving up his usual composed self as he saw that even Kuro was still lying and resting peacefully on his tights. "You're sleeping more than 10 hours a day and you're still unable to wake up on time."

Yukio lifted up his blanket, chasing away the familiar of his older brother, and let running his left hand on his half-naked body. "When will you grow up, Nii-san?" said the youngest brother, before grabbing the tip of his tail violently.

"Yukio, you bastard." jumped out Rin. "Don't wake me up like that, it fucking hurts."

"I wouldn't wake you up that way if you woke up like a normal person. "

"Even so..." complained the eldest brother, massaging his tail. "What time is it?"

"7 o' clock." sighed Yukio as he looked at his watch, annoyed. "You have thirty minutes left before my class starts."

Getting up, Rin stretched himself and put his white shirt on. If he didn't want to be killed by Yukio, the exwire should hurry up like – right now. His little brother might seem the quiet type but he wasn't, oh hell, he wasn't. Since they moved in together, Rin had had a good overview of who was the exorcist – dark, aggressive, so violent he was afraid of teasing him sometimes.

"Just hold on a sec."

Childhood days were over, Yukio wasn't a cry baby anymore, and somehow, Rin missed it. Yukio coming in his bed (because he was afraid of the dark), Yukio clinging to him, Yukio calling his name. All of those gentle sides of him that had disappeared...

That's why the eldest brother ran to the kitchen, took away the bento he had prepared yesterday and gave it to his little brother, who was waiting for him, sitting on a chair, in their bedroom.

"Hey, four-eyed idiot." called out Rin with a grin. "Take this with you."

Yukio's blue eyes widened as he saw the colorful box and the chopsticks that his older brother were handing to him, surprised.

"I've noticed that you've been skipping meals lately... Something's wrong?"

Yukio smiled, adjusting his glasses. It was hard to hide things from him now that Rin was older. The exorcist had to be more cautious, it woud be a catastrophe if his cover was blown up yet it was hard to control himself when Rin was acting so... cute.

"No." blushed the youngest male. "But thank you, Nii-san."

"Don't mention it."

Feeling relieved, his older brother put his red case on his shoulder and headed to the exit. Rin was still dense, after all, thought Yukio as he followed him.

 **X**

Classes had ended quite smoothly, if we took out the fact that Rin had fought with Bon, that Shura had barged into his class or that almost everyone hadn't understood the basics of creating a health potion – it could have been worse.

Yet, his day wasn't over. Yukio had still to meet with Mephisto who was currently missing; the director wasn't in his office nor in his favorite playground.

"What a pain."

Well, being a teacher at True Cross Academy turned out to be even more tiring as being an exorcist. He sighed but stopped his hurried steps as the exorcist caught sight of his older brother lying under the trees, outside, Yukio leaned closer to the window, with Shiemi.

It was bound to happen – someone else being infatuated with Rin... Yukio knew that his feelings were unrequired, and especially wrong, but that didn't mean they would disappear instantly with a magic trick.

"Do you like what you see?" stated a cold and mocking voice.

Rin was smiling. Shiemi was laughing. Leaves falling around them.

"Indeed, what a beautiful scenery." answered Yukio with the best poker face he could mutter.

At least, Rin was happy, that was all matter.

"I was searching for you." said the exorcist, facing Mephisto after he had turned himself around and averted his gaze from his older brother. "Where were you?"

"Oh you know, the usual, sneaking into secret rooms, spying on bad people." laughed the director of the True Cross Academy. "Anyway, shall you give me your reports on Rin Okumura?"

"Here?" frowned Yukio, pondering the fact that they were in a large corridor. No one should know that his brother was a demon, no one. "Aren't you a bit careless?"

"My bad, habits die hard." smiled Mephisto, before morphing himself into a dog.

The teacher sighed.

Oh hell, he was right.

 **X**

When he came back home, Yukio was exhausted – and frustrated. He didn't know if Rin was already here or not but he locked himself in the bathroom. He needed to cool down, he needed to forget what he had seen earlier that day in school.

Why was he the only one to struggle so hard?

He opened the tap and entered the shower, cold rain running on his skin, wiping away the dirt and the sweat. What was going wrong with him? Usually, his mask didn't break so easily, usually he could handle his emotions – his anger, his fear. Shiro had trained him for that purpose at first before Yukio realized that he was raised as a weapon for the sake of Rin...

The young male rubbed his legs, his tights and then his crotch.

Since when had he felt like this? Since when his love for his brother had become so complicated – so disturbing, filthy and twisted?

He was rubbing harder – it felt wrong.

Yukio didn't know what to do. He was protecting Rin in his father's stead yet his emotions, dark thoughts and repressed feelings were going in the way. He was his little brother and at the same time, he was his teacher at school, and to add even more variables to the equation, Rin was a demon whereas Yukio was a human and an exorcist.

How could this be even more complicated?

He stood in front of the mirror, looking at his reflection, thoughtful.

"I'm stupid..."

The only thing Yukio was sure was that, no matter what, he wanted to see the smile of Rin.


	2. Invitation To Madness

**A/N: ** Hi there ~ Here's the second chapter of DBY! I wanted to write more so that I don't finish on a cliffhanger but I don't want to rush this fic so the chapter became like this XD And seeing how I'm writing this story, it's already longer than I planned *sigh* And I want to write the twincest so bad but I can't now T_T Need to develop the relationship first *cries* Anyway, thank you for supporting me Stacy20 and ruinedprincess, that's what keeps me writing!

* * *

 **Devil Beside You**

 _Chapter 2: Invitation To Madness_

There was a little blue bird that couldn't fly any further than the ceiling of the golden sky – its cage. Even though the air outside seemed fresher, it thought that its home wasn't too bad (it was safe) until its owners came to take the little blue bird away, away from the window, far away from its dreams.

When they broke up its shell, they enjoyed locking the little blue bird in a room, in a huge dark room where there were no windows, no air – only them and the naked darkness.

There, it would sing in the rain. There, it would fly high and hit the bars until it was too tired to move, until it became simply useless to even resist. There, the little blue bird thought it wanted to die.

Unwittingly, the pain was growing into something much more dangerous and uglier, scars, memories that wouldn't fade, sounds that couldn't be forgotten.

"Come on, fly. "

"Let me hear you sing, my little blue bird."

In fact, the little blue bird couldn't fly, its wings were cut; they had been torn apart by its owners so that it could never escape them, so that it was forever theirs.

"We love you."

That's why one day, the little blue bird didn't hesitate to jump into the hands of that unknown person, even though the palms were bloody.

The sky wasn't high in that cage too.

 **X**

He was lazying around shamelessly; his homework was stacking on his desk, his dirty clothes were scattered everywhere, and his gaze laid on Kuro who was playing with a water bottle top, getting hyped each time he lost its trace.

Rin was bored to death.

His little brother had gone on a mission and, of course, he had refused to take Rin with him, saying that it was top secret, saying that it wouldn't take long or, with that playful and annoying grin of his, that he should focus on what he could do at the True Cross Academy to become an exorcist. Yukio could have said that he didn't want him to come with him, it was the same, groaned Rin as he grabbed a mangas on the shelf with his remaining energy.

Yes, boredom was that overwhelming and so was the summer heat.

Maybe his little brother was still holding a grudge against him for their father's death? He might be dense but Rin had noticed that Yukio's behavior towards him had changed, especially since they had moved in together. Yukio would always act as if Rin was made of crystal, as if he needed to be protected, it was annoying.

But it wasn't as annoying as his little brother looking like their father; Rin had always admired Shiro and seeing Yukio taking after him more and more day by day was... painful. His little brother was taller than him, he was already a first middle class exorcist while Rin wasn't worth anything.

He kept on turning the pages.

Had Yukio done all of this to kill him someday because, after all, he was Satan's son?

The exwire would never forget the day his little brother had pointed a gun at him and told him to die, it would resurface insidiously when he expected the least, and his mind and his body would react to it – Rin would do anything as long as it let his anxiety drown itself in his heart.

Glowing tears were forming in his eyes. "Why did she have to die?" sobbed Rin, water overflowing his face.

He should read less tragedies though.

 **X**

Bang.

Blood was splashing on his boots. Yukio had killed the last one of them or so he thought when he caught sight of a twisted shadow, unknown forms and feathers dancing in the air, along with the thin silhouette of a young girl.

After several seconds of reflexion, the exorcist ran in the dark alley, equipped with a gun loaded with acid bullets. It was gone yet the girl was lying on the floor, breathing in, breathing out.

"Are you okay?" asked Yukio, concerned as he saw some marks of ink, demonic figures slowly spreading on her skin. "Can you hear me?" They were all over her face, drawing a mask.

Yukio didn't wait any longer, he opened one of his leather satchel and applied some herbs on her face to remove the curse or whatever it was while he was chanting a cleansing spell.

"Thank – thank you." she whispered, opening her eyes.

Relieved, he smiled. It was in those kind of situations that Yukio was happy to have attained a meister in Doctor, he didn't want to think what would have happened if he hadn't.

"My name is Michizuki Sae. What's yours?"

"Okumura Yukio."

"So Okumura-san is the name of my savior." giggled Sae, grabbing tightly his arm.

Apparently the pain had vanished all of the sudden, noticed the exorcist, annoyed.

"I only did my job." stated Yukio not in the least enthusiast.

He knew all too well where this was going, it was the same at school; all girls were fawning over him and it was annoying – plus, it didn't seem like it but Yukio didn't know how to behave around women (although Shura couldn't be considered as a typical one) and it wasn't as if the young male had faith in his looks either. So what was this sorcery? Why they were always attracted to him?

"What is your job?"

"Isn't obvious?" laughed Yukio softly. "I'm an exorcist."

Her eyes screwed up a bit, and a sparkle of interest lightened her face as she studied him closely.

"So I wasn't crazy, they really do exist."

Yukio nodded, before he picked up a blue feather at her feet.

"Let me come with you, please. I'm scared."

Something was wrong yet he couldn't pinpoint it.


	3. A Tragic Instinct

**A/N: ** Sorry for the delay, folks :o Didn't think I will be so overworked ;-; Last chapter before things starting to get serious XD Hope you'll stick with me until the end with this fic ~ As always, thank for the support, godess bubbles, Natsume-Erika and Crye of the Fallen :3

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 **Devil Beside You**

 _Chapter 3: A Tragic Instinct_

Running and running, the little girl didn't look back. Excuses, dreams or nightmares – all of this would get her nowhere. Her pursuers were not far behind, the sound of the edge of their sabers sharpening on the walls ringing to her ears, yet she had some hope.

When his eyes laid on that human child in the street, wearing some torn blue clothes and pretty purple bruises, he could smell her soul burning, he could hear it cracking as if he had taken a bite of it, and it smelled so good.

She was still believing that someone would save her.

The demon changed his shape, hiding his fangs and his horns, before revealing himself in front of her as a innocent and reassuring teenager – tall, blonde hair, warm smile yet bright red eyes that narrowed slightly when he asked with a soft voice:

"Are you lost?"

She looked up at the long road behind him, empty. Her thoughts only focused on the idea of keeping on running, (and if she was unable to), on walking or crawling.

"No, I'm not." whispered the child.

Blind escapism. Laughing, the demon in disguise knelled while he looked more closely at his prey who was averting his gaze, unknowingly shivering when he reached out to her.

"It's not good lying, you know."

She was beyond salvation.

His prey averted his gaze, shaking. Of course she couldn't tell him the truth, it was too horrible – too wrong for her own mind, and even if she wanted to explain herself, how come a child of seven years old would understand properly the concept of rape?

"I can't tell you."

He smiled.

"Is it a secret?" said the demon, amused, caressing her dislocated shoulder with the tip of his fingers, "that they touch you here and there?"

She nodded.

"Don't worry."

Smooth and hypnotic. Words were coaxing her, getting under her skin.

"I'll give you wings so that you can fly away from your cage."

"Really?" asked the child, eyes shimmering.

"Really."

She took his hand.

Humans were, indeed, too easy to possess.

 **X**

Three days... Yukio had been gone for three days because of that stupid secret mission, mumbled Rin as he looked through the window, not paying attention at all to his surroundings. His brother had said it wouldn't take long, he had said it would be a piece of cake but it was now clear that it wasn't – Rin could feel it.

Maybe it was a special ability that had awakened since he turned himself into a demon but (and he didn't know how) Rin was drown to others' pain, it was like he could hear their heart break, somewhere in the distance. Everytime one of his friends was suffering, the exwire would sense them, sweet and mellow voices filling his ears.

And it was unbearable.

Because no matter how much he wanted, he couldn't help them; Bon and Izumo were too prideful to admit when they needed help, Shima and Konekomaru, for unknown reasons, didn't open their heart to him that much and Yukio...

"Stupid four-eyed brother."

He was like a total stranger, sometimes.

"Rin, what's wrong?" asked Shiemi, whispering, to avoid to get caught by the teacher.

"Well..." started the young man, hesitant, because he didn't want to worry her as well. "It's Yukio. He hasn't come back yet."

The daughter of the exorcist supplies store smiled. She had always found the way the Okumura brothers cared about each other cute, it almost made her jealous of being an only child.

"I'm sure he's doing fine. Believe in him."

He sighed. It was easier said than done.

"Yeah, but you know, I can't help –"

"Would you please be quiet? I'm trying to listen to the old geezer." cut off Suguro, sitting behind them, annoyed as he was nibbling the tip of his pen.

"We are not even loud."

"True. Shiemi isn't, but you are."

If Rin was in his normal state, he would have already picked up the fight yet he let it go and kept calm, although some dissonant voices were calling him – despair.

 **X**

In the end, he had accepted to follow Sae. Yukio's mission was to eliminate the demons that had been spawning in a residential district in Tokyo, and since the enemies were as weak as gobelins, Mephisto assigned him on the case alone but maybe it was a mistake.

It had been days he was going in circles, unable to find the source of the curse, and the death toll didn't stop increasing.

"We're almost here." said the young girl, pointed the deserted building.

And Yukio was ready to follow anyone, as long as he found it. Ivy was covering the steel walls, broken windows letting pass the moon lights, as the hot air was suffocating him. It was weird.

"At last, you come to see me." rejoiced Sae in front of him, lifting her hands in the air. "You're so cold, Okumura-san."

Yukio frowned, holding his gun right away in his holster, ready to draw it. He knew something was wrong with her, that's why he had tried to stay away from her those past days but she was always coming back to him, trying to lure him in obvious traps – like this one.

"Drop the act."

Blue birds flew towards Sae, chanting ineffable cries.

She was possessed.

"Will you kill a human without hesitation, exorcist?" grinned the possessed girl, a smile twisting her face. "I may own her body but she's alive nevertheless. Can you pull the trigger?"

He shot at the bird, on her left shoulder.

"She can't be saved." deadpanned Yukio.

"Oh poor little thing..." said Sae, watching the bird on the floor, flapping its wings weakly in a pool of blood. "You just killed a 7 year-old-girl."

Yukio's eyes widened.

"Don't tell me..."

"Yes." laughed the demon. "Appearences are deceptive, my little birds used to be beautiful girls who made a deal with the devil in exchange of freedom. Isn't sweet?"

His hands were shaking. What could he do?

 **X**

Believe in him, Shiemi had said. The day had been particulary long and painful for Rin's heart; the haunting sounds wouldn't leave him alone, and Rin wasn't the kind of person to let himself die of worrying. If Yukio didn't come back tomorrow, he would go to his research wether his stupid brother liked it or not.

Undressing himself, Rin was about to sleep when his younger brother opened the door of their share bedroom. Freaked out, he wanted to yell at him yet he remained silent when Yukio came closer to him, his clothes stained of blood, his face pale. What the hell had happened?

He drew Rin closer to him and hugged him tightly.

"Nii-san, can we stay like this?" whispered Yukio, his voice broken.

The oldest male was taken aback. All the things he wanted to tell him, why did he leave him behind, why did he take so long, why did he tell him nothing, why, why, why, died on his half opened lips.

"Yes." finally answered Rin.

Yukio cried on his shoulders, silently, but he could feel the salty water soaking his skin – it hurt.


	4. Invading Suspicion

**A/N: ** Hi there ~ Here I am dropping randomly the 4th chapter XD I'm so sorry for the waiting but I guess it will continue to be that way for a while... It's hard to find the time to write with all the work I have :( Crye of the Fallen, Natsume-Erika, and trueblueyou223, thank you for the support :3

* * *

 **Devil Beside You**

 _Chapter 4: Invading Suspicion_

"Rin and Yukio are absent today..." noticed Shima, surprised. "That's rare, especially for the freaky teacher." added the exwire as he sat next to Shiemi who was picking gracefully some tamagoyaki with her chopsticks.

"Yeah, I've noticed that too. I hope they are okay..."

She swallowed the wrong way though; it had been days that Yukio had been on mission to God-knows-where and that his older brother had been worried sick (even if Rin had tried to deny it), the blonde girl couldn't help feeling sad for them.

"What do you mean? Do you know something?" asked Shima, narrowing his eyes imperceptibly.

Shiemi hesitated to give him an answer, looking thoughtfully at her food. Should she tell him or not? She didn't think that Rin would like the fact that she talked to everyone about his life.

"Not really. "

Tilting his head a little, Shima smirked – the female exorcist was such a bad liar, he could see right through her. For now, the exwire would pretend that he didn't know anything and decided to act like usual, which meant, being a carefree pervert.

He moved on to the right and tried to pass his hand slowly behind her back, yet before he could do anything else, Bon and Konekomaru appeared as if they had sensed the danger.

"Now that Rin is not here, you're molesting her... Don't you feel ashamed?"

The blonde girl stopped eating and looked at Bon, a bit lost, not understanding the situation. It was rare that those people were seeking for her company. Usually, she ate her lunch break alone or with Izumo when the tamer allowed her to.

"At this rate, I will have to purify your soul." added Konekomaru as he hit him gently on the head.

"Guys..." Shima laughed, fooling around even more. "You're exaggerating. I was just feeling lonely."

"No, I'm not. It's dangerous to let you alone with girls..."

"Well, in that case..." offered Shiemi, smiling while she was watching the boys arguing playfully among themselves. "How about we eat together more often?"

"Great idea."

Shima took the opportunity to redirect the conversation to the topic he was really interested in: the Okumura brothers.

"I don't think Suguro will be calm enough to eat next to Rin though."

Bon frowned.

"I can behave myself, it's him the problem. Where is that offender by the way? Skipping classes?"

"Who knows?" said Shima, shrugging his shoulders.

The daughter of the exorcist supplies store could stay silent but the pink-haired male would discover sooner or later what those so called twins brothers were hiding from everyone – he wasn't a fool, it was only a matter of time.

 **X**

The following day after that night, Yukio had acted like nothing had happened.

A faint smile on his lips, a cup of coffee in his hand to soothe his exhaustion and he felt like he was feeling better, back on track, or so he thought when the teacher let the porcelain cup hit the floor, the black liquid slowly dispersing amid the broken pieces.

"Shit." cursed Yukio as he moved to look at the mess he had made.

The crushing noise woke up Kuro who jumped out from Rin's bed whereas, without frowning, his older brother was watching him, upset. Cries. Guns. Blue feathers on a black coat drenched with blood. Vivid images were invading his mind as he remembered yesterday's night when his little brother had tried painfully to clean the blood on his clothes (on his face, on his hands), when Yukio had closed his eyes to sleep, never stopping moving under his blanket, tormented.

"Let me help you." said Rin, coming closer to him. "You haven't still recovered."

"I'm okay." laughed the teacher.

"You're okay..." repeated Rin, watching his hands shaking. "Are you fucking kidding me? Why are you shaking then?"

"Drank too much coffee, I guess."

Rin didn't know what to do – Yukio was joking casually, keeping on acting the perfect exorcist role and it annoyed him to no end. Why would Yukio refuse to depend on him? Rin was his older brother, after all.

"You're impossible." he sighed, taking the exorcist's face between his hands despite the fact that his little brother was taller than him.

"What are you doing, Nii-san?"

Rin glared at him, intensifying their eye contact. He never thought that he would use his demonic power of perception on Yukio to understand him better but the exorcist was so stubborn that he had no other choice; all he could grasp from his soul was a confusing storm, which wasn't actually really useful to Rin but still, it proved him that his little brother needed help.

"If you want to cry, just cry, stupid four-eyed idiot."

Yukio pushed him away, averting his eyes.

"I don't want to cry. I have already done it enough yesterday anyway."

"That is not what your look is saying, be honest."

There was no way in hell that Yukio would tell him the truth, wouldn't he?

"Tell me, Nii-san..." he whispered, though.

Because he had to be strong for both of them – he had to be better, stronger than Rin now that Shiro was gone yet it had been so long that he had kept this up, so long that he had been concealing his feelings, so long...

"Am I still humane after having killed more than two hundred persons?"

He broke down.

"What do you mean?" blinked Rin, surprised.

Yukio swallowed, before sitting himself on the desk (in order to not lose his ground) where he had been correcting the assessments of his students a few minutes ago.

"The mission. It went wrong. I had to shoot all the birds that she was throwing at me."

"I don't see any problems with –"

"Those birds were children, little girls,"cut off the exorcist, his tone serious. "and I killed them all, every one of them, without hesitation."

Silence filled the room suddenly, and Yukio regretted immediately what he had said, cursing himself for being so weak, until his older brother broke the ice with a mischievous smile:

"So what? You want me to call you a demon now? You're stupid, Yukio." grinned Rin as he closed the distance between them.

"But..."

"It doesn't change the fact you are my brother, my only family, and that I trust you." the exorcist put his right hand on Yukio's head, patting it as if his little brother were still a child. "Knowing you, you won't pull the trigger unless it is necessary so I trust your judgment."

"Nii-san," whispered Yukio, touched.

If only Rin could know and accept all the secrets that he was hiding, thought the youngest male bitterly as he smiled to his brother.

"Thank you."

If only...


	5. Heart Rate

**A/N:** Hey guys ~ I'm still alive XD My internship is over so I have some time to write :3 With this chapter, we are going to the next level, so **be aware of the rating**! As always, thank you  godess bubbles, Natsume Erika, Akita Akira and Crye of the fallen for your reviews, it is always heartwarming to read. Thank you also everyone who is following me, there more or less fifty people now! I feel blessed :3

* * *

 **Devil Beside You**

 _Chapter 5: Heart Rate_

Glowing blue embers, ashes, consuming fire leeching off his frustration, Rin wouldn't stop training. He needed to be stronger, because what hurt him the most was that he could do nothing to help his little brother, nothing.

"Burn!" screamed Rin as he released a ball of fire towards the wall.

During his training, he was supposed to light up the wick of a candle without making it melt yet, considering what had happened with Yukio lately, he stopped focusing on the control of his flames and lost it all.

 _Who does he think I am?_

Rin wasn't naive. He knew Yukio was hiding some (several) thing(s) from him but no matter what he did, he wouldn't get the truth. He had waited, he had cheered him up, he had been impatient, angry, sad. Still what was between them was this unexplainable distance, which was driving Rin mad, which even made him doubt of himself – was he a failure as his older brother?

He kept on slashing the air with his sword, invisible monsters around him, until Rin collapsed from exhaustion. He only wanted to be stronger...

When he opened his eyes, Yukio was looking at him with concern, "What happened to you?"

"I was..."

Trying to be useful to you, was tempted to answer Rin.

"Training." finished the black haired male.

"I thought so." sighed Yukio as he removed his hand from his older brother's forehead. "Can you not train like a normal person?"

The exorcist couldn't admit to himself but he had been scared. When he had found Rin, still, lying on the ground, with his sword next to him, his heart had skipped a beat.

"A little sweat never hurt nobody."

His older brother laughed. It was typical of Rin, being unreasonable thought Yukio.

"Talking about sweat, you should take a shower, you stink."

"Why don't you take it with me then?" said Rin before getting up with a grin."You stink too."

He froze, the blood was coursing through his veins, his heart was pounding against his chest.

"What-what-what are you saying?!" burst his little brother, embarrassed.

"Come on, don't be shy. We used to bathe together when we were younger."

Rin missed those days; when they were playing all day long in the backyard of the church, when they didn't know the world was split into two – humans and demons, when their father, the greatest exorcist ever, was still alive and protected them, when Rin and Yukio were simply ordinary people.

"Precisely, we were kids. Now we..."

But they never had been one.

"What's different now?" asked Rin, frowning while staring into his green eyes.

 _Everything._

Yukio stayed silent, trying to suppress all the signs of nervousness. He was way too focused on this task to notice that his older brother took this opportunity to drag him in the bathroom, the giant one at the first floor which had a hot spring outdoor, and when Rin started to undress himself, Yukio knew he couldn't run away.

 **X**

Thick mist, hot heat haze sticking to his skin, electrifying his senses as he entered into the crystal clear liquid. The water was deep, so deep Yukio wanted to drown in it yet he couldn't. His back was against the stones, and in front of him was Rin, swimming, letting himself floating away with the waves.

"It feels good, doesn't it?" whispered his older brother, completely relaxed.

He could see everything; his long thin legs, his strong inner tights, his, Yukio averted his gaze, sex.

"Yeah..."

"I can't hear you." said Rin, coming closer to him. "What did you say?"

"I said it felt good." shot back Yukio, his cheeks red. "Why are you so clingy today?"

"Because we are drifting apart."

Why was his brother so honest? Why was he so blunt? The younger male was upset, suddenly his words broke his inner barriers, his resolution, his will to not touch him because if he did, it would trigger what he had been fighting against for so long – the demons within him.

 _Calm down._

Rin was handsome, otherworldly cute, so innocent a nd pure he would eat him up right now if he could. If he could let everything go, forget that he was his brother (his student, a male and a demon), Yukio would kiss his neck, lick his adam's apple and his well-defined jawline, before going higher, and suck his lips. It would be so, so good, tasty, he would want to have more and force his tongue into his mouth, which couldn't shut up.

"Rub harder, Yukio."

Yet, the younger male had taken the soap, gone behind him and started to wash the back of his older brother silently.

Rin didn't know what the exorcist was thinking, the situation didn't seem to bother him, Yukio hadn't answer him, he had contented himself with what Rin had said: the distance between them. Had he opened up to him for nothing?

Yukio slowed down his movements, trailing his fingers over his shoulders, scars and blue marks staining his skin – ecchymoses due to his hard training.

"Nii-san." whispered the younger male, a strange excitement in his voice.

Maybe the heat was clouding his mind, maybe the massage of Yukio was too good but Rin closed his eyes, and he felt the arms of his brother circling his frame, he felt the breath of Yukio against his ears, and he heard:

"You are so dirty."

Pressing his chest against the exwire's back, the tail of Rin was stuck in between but one of the arm of Yukio let go of his neck and grabbed it.

"No matter how hard I wash you, you're still so dirty." said the exorcist, rubbing the tip of Rin's tail between his fingers. "It's annoying."

The older male gasped, suddenly waken up from his drowsiness, "Stop touching it."

He kept doing it though, harder, and Rin couldn't help moaning. It was his weakest point, after all, and it was sensitive, way too sensitive after what Yukio had done to him – his touch was burning him, making his whole body tremble.

"Yukio..." sighed his brother, helpless. "It's embarrassing."

"Why is that? I thought that bathing together was normal."

It was not normal. Something was off with his younger brother's behavior; Yukio never talked to him like that, his voice sounded deep, smooth and silky – and feeling aroused by it, and by what he was doing to his body was not normal either, realized Rin, upset.

"It is. Just –"

Without warning, the older male stretched out his hands to hang on the edge of the hot spring. He wanted to get away from Yukio's stifling heat, his strong embrace, but he was still attached to him in a way. His younger brother was holding his tail with one hand, playing with it, up and down, as if it were his own dick, and he was exerting a pressure on his shoulder with the other hand, which made his back arch painfully.

Rin didn't know what was wrong with him (or with both of them?), with his demoniac body and everything else because surprisingly he was aroused. He was hard because of what his brother was doing to him – it was disgusting.

"Just stop touching it, you fucking tease. Do you want to turn me on, four-eyed idiot?!"

Ashamed.

Yes, Yukio wanted to make him feel how he felt every night, how his love and desire for Rin were consuming him and driving him crazy, how, if he could, he would go in his bed and kiss every patch of his skin, how he would make his way into him, nice and slow, taking care about not hurting his dear brother, also how he would take the time to please him, to blow him up until he came, how he would play with his tail and bite it to turn him on again so that he could have a second round.

Yet Yukio got a hold of himself.

"I'm sorry, Nii-san." he said, before releasing him. "My prank went too far."

Rin turned around and faced his younger brother, annoyed. "I guess I am to blame for forcing you bathing with me."

The exwire only wanted to spend time with him, like before, before their family became so dysfunctional. He had made a move to be closer to Yukio but it felt like it was the opposite instead; Rin couldn't understand his twin brother anymore, he was a stranger to him unless he decided to speak his mind – a thing Yukio did very rarely nowadays.

"Don't blame yourself, it doesn't seem like it but I enjoyed it." smiled Yukio with the best poker face he could make, sadness, lust, pain, blending and drowning together in his heart all at once. "It reminded me of the past."

Rin wanted to add something but Yukio cut him off, and said, getting out of the pool. "I'm going to sleep."

As he disappeared in the hot haze, the exwire was watching his younger brother's back – taller than him. Growing up wasn't easy, Rin had to deal with complex and incomprehensible feelings.

 _Stupid four-eyed idiot._

He needed to jerk himself off.

 **X**

How could he face Rin after that?

Yukio wanted to bury himself, he wanted to never open his eyes ever again. It was a miracle that he hadn't gone too far and had stopped in time before doing the unthinkable – that forbidden act, a sin.

Yukio turned around in his bed, tormented by his guilty pleasure and conscience. He had always controlled himself, even though it was hard, he had always resisted the urge to touch his brother that way, because Rin had grown up, he was older and he would understand it eventually – and that, Yukio couldn't let it happen.

Their relationship would be destroyed, but what was their relationship exactly? Yukio was his brother and his teacher but he was torn apart by his unrequited love for him as well. How should he behave? The exorcist didn't know anymore.

Everything was blurry, everything went black.


End file.
